Expression And Clinical Significance Of SALL4 In Oral Squamous Cell Carcinoma

Objective:To investigate the expression and clinical significance of sal-like protein 4(SALL4)in oral squamous cell carcinomas(OSCC)by analyzing the relationship between SALL4 and the clinicopathological parameters of oral squamous cell carcinomas at the mRNA and protein level.Methods:Based on the 50 cases of OSCC operated by oral and maxillofacial surgery in Stomatological Hospital of Shandong University,Qilu Hospital and Shandong Provincial Hospital from the time period of Feb 2014 to that of Aug 2015,we compared the tumor tissue cut from OSCC specimens with normal mucosa from the edge of these specimens.The expression of SALL4 in OSCC was investigated at the mRNA and protein level by RT-PCR,western blotting and immunohistochemistry.In addition,the relationship between the expression of SALL4 protein and relevant clinicopathological parameters was explored and analyzed.Gender,age,clinical stages,the tumor differentiation degree and lymphatic metastasis degree were included in the parameters.SPSS 17.0 software package was used to analyze the data,in which P<0.05 is recognized as the statistically significant difference.Results:1.The expression of SALL4 mRNA in OSCC and normal peritumoral tissues detected by RT-PCRThe expression of SALL4 mRNA in OSCC was significantly higher than that in normal peritumoraltissues(P<0.05).2.The expression of SALL4 protein in OSCC and normal peritumoral tissues detected by western blottingWith the β-actin protein as the specimen quality reference,differences in expression level of SALL4 protein in OSCC and normal peritumoral tissueswere observed.Specifically,the expression in the former was significantly higher than that in the later(P<0.05).3.The expression of SALL4 protein in OSCC and normal peritumoral tissues detected by immunohistochemistryIn the specimen of OSCC patients,we detected positive SALL4 expression,which was located in cell nucleus in a brown granular form.The positive expression rates of SALL4 in OSCC and in normal peritumoraltissues were 64%and 14%respectively.The expression difference was statistically significant(P<0.05).4,The relationship of SALL4 protein expression and relevant clinicopathological parametersGender,age,clinical stages,the tumor differentiation degree and lymphatic metastasis degree were included in the parameters.There were 15 males and 17 females with positive SALL4,and 8 males and 10 females with negative SALL4.Among the patients with positive SALL4,14 of them were at the age of 56 or under,and 18 were over 56,while among those with negative SALL4,7 of them wereat the age of 56 or under and 11 of them were over 56.Among the positive SALL4 patients,20 of them were at the clinical stage(Ⅰ+Ⅱ),and 12 were at the(Ⅲ+Ⅳ)stage;while among the negative SALL4 patients,there were 16 at the clinical stage(Ⅰ+Ⅱ),and 2 of them at the(Ⅲ+Ⅳ)stage.Among the positive SALL4 patients,5 of them were poorly differentiated,8 were moderately differentiated,and 19 were highly differentiated.Among those with negative SALL4,2 were poorly differentiated,3were moderately differentiated,and 13 were highly differentiated.17 patients with positive SALL4 showed lymph node metastasis,and 15 patients with positive SALL4 showed no lymph node metastasis;4 patients with negative SALL4 showed lymph node metastasis,14 patients with negative SALL4 showed no lymph node metastasis.The relationship between those parameters and SALL4 positive expression was statistically analyzed.The results showed that the expression of SALL4 protein was closely related to the clinical state of tumor(P=0.046,P<0.05)and metastases(P=0.034,P<0.05),and unrelated to the clinicopathological parameters such as gender,age and tumor differentiation degree.Conclusions:1.The expression of SALL4 in OSCC is higher than that in normal peritumoraltissues.SALL4 has some effect in the clinicopathological diagnosis and differential diagnosis of OSCC.It may be used as an auxiliary diagnosis marker with good sensitivity and specificity.2.SALL4 might play some roles in the metastasis of OSCC.However,the exact regulating mechanisms and its biological function remain unclear,which needs to be further investigated.